Explanations of the DAMPE high energy electron/positron spectrum in the dark matter annihilation and pulsar scenarios

• 来源期刊: 中国科学（物理学 力学 天文学）
• 年，卷（期）: 2018,（10）
• 页码范围: 19-29
• 页数: 11页
• 语种: 中文

摘要

Many studies have shown that either the nearby astrophysical source or dark matter (DM) annihilation/decay can be used to explain the excess of high energy cosmic ray (CR) e±,which is detected by many experiments,such as PAMELA and AMS-02.Recently,the dark matter particle explorer (DAMPE) collaboration has reported its first result of the total CR e± spectrum from 25 GeV to 4.6TeV with high precision.In this work,we study the DM annihilation and pulsar interpretations of this result.We show that the leptonic DM annihilation channels to τ+τ-,4μ,4τ,and mixed charged lepton final states can well explain the DAMPE e± spectrum.We also find that the mixed charged leptons channel would lead to a sharp drop structure at ～ TeV.However,the ordinary DM explanations have been almost excluded by the constraints from the observations of gamma-ray and CMB,unless some exotic DM models are introduced.In the pulsar scenario,we analyze 21 nearby known pulsars and assume that one of them dominantly contributes to the high energy CR e± spectrum.Involving the constraint from the Fermi-LAT observation of the e± anisotropy,we find that two pulsars could explain the DAMPE e± spectrum.Our results show that it is difficult to discriminate between the DM annihilation and single pulsar explanations of high energy e± with the current DAMPE result.